Combination square and protractor



Oct. 9, 1951 M. u s 2,570,356

COMBINATION SQUARE AND PROTRACTOR Filed April 5, 1949 M v 13 ll? z L INVENTOR.

MICHAEL Luls ATTORNEY Patented Oct. 9, 1951 UNITED STATES PATENT OFFICE" COMBINATION'SQUARE AND PRoTRAo'roa- Michael Luis, Cleveland, Ohio Application April, 5, 1949, Serial No. 85,649

1 Claim. 1 V

This invention relates to improvements in ma chinists, or carpenters combination squares and has for one of its primary objects to provide in one complete unit a device that will perform the required functions of a square, ruler and protractor.

Another objectis to provide in such a unit, in addition to a pair of stationary square arms, either of which may be used as a base, an arm adjustable on the end of one of the stationary arms that is movable throughout a 90 degree angle toward the other stationary arm and also useable as a base in an adjusted position.

Another object is to provide in such a unit a pair of separate spirit levels, one for one of the stationary arms and the other for the adjustable arm when each is used as a base.

A further object is to provide, in addition to the stationary square arm, a second arm that is adapted to support a removable ruler, a portion of the length of the second arm being arcuately adjustable to form a part of the protractor.

With the foregoin and other objects in view, the invention resides in the combination of parts and details of construction set forth in the following specification and appended claim, certain embodiments thereof being illustrated in the accompanying drawings, in which:

Figure 1 is a view in side elevation of the device, showing the body portion, the two levels, the rigid stationary arm, a second arm carrying a ruler, the outer swiveled portion of the second arm being shown in full lines to a 45 degree angle and in dotted lines to a 90 degree angle;

Figure 2 is an end view of the device taken from the right end of Figure 1; and

Figure 3 is a view in section taken along line 3-3 of Figure 1.

Referring more particularly to the drawings, the combination square and protractor unit comprises a body portion I having a pair of square arms 2 and 3 with faces 4 and 5, respectively. Face 5 of arm 3 is slotted to removably receive a graduated scale rule 6 and secured therein by a suitable clamp actuated by a knurled hand knob 1.

Body portion I also carries an arcuate channel 8 to slidably receive a graduated are 9 that is rigid with an arm I0. This arm H! has two forked ends [3 that straddle arm 3 to mount arm Ill so that it rotates about a pin 1 I extending .through arm 3. Arm ID has a face I2 that is slotted in like manner to face 5 to removably receive the ruler 6. v

Channel 8 is provided with a window I8, in vertical alignment with pivot pin II, as viewed in Figure 1 so that the graduations of degrees of angle on are 9 may register therewith and be visible therethrough. The are 9, after adjustment thereof in channel 8, may be secured in such adjusted position by hand operation of a knurled knob H) which is screw threaded to a T-shaped bolt 26 embedded in are 9 and passing through channel 8.

In Figure 1 in full lines, the arm I9 has been adjusted so that its face I2 is at a 45 degree angle to face 5. Thus, the number 45 appears in window I8 of channel 8. That portion of are that is within the channel 8 is indicated immediately to the left of window H3 in dotted lines at 9. The are 9 is graduated in degrees from 0 to degrees and the arc is swingable in the channel throughout 90 degrees about pivot pin H. In other words, the arc is swingable from a position where its face I2 is a flush continuation of face 5 to register 0 angle, throughout a clockwise movement to that shown in dotted lines in Figure 1, in which latter position the graduation 90 will appear in window l8.

It will be readily understood that the graduations on arc 9, while shown reading only from left to right from 0 degree angle to 90 degree angle, the same, in accordance with usual, may in addition also have like graduations reading from right to left from 0 degree to 90 degrees.

While I have shown a specific type of protractor arrangement wherein a graduated are 9 slides in and out of channel 8, it is to be understood that I may prefer to provide member H with a series of calibrations of angle degrees and supply pivot pin II with a suitable scribed pointer to register therewith to denote the degree of angular adjustment of arm 12 with respect to stationary arm 3.

Two spirit levels l6 and I! are carried by the body portion I. Spirit I6 is used in the usual way with faces 4 and 5 of the two respective stationary square arms 2 and 3. Spirit level II is used in conjunction with face 12 of the pivotally adjustable arm Ill to insure positive level of a reference plane when using the face I2 on an inclined surface to obtain a protractor reading of the inclined surface.

I claim: 7

In combination in a measuring device, a square having a body portion with two stationary arms includin outer base reference faces extending at right angles to each other, one of said arms being slotted at one end and the second of said arms being slotted at one end and the second of said arms being slotted along its face to removably receive a ruler, a downward extension on the outer end of said second stationary arm having a pivot means located inside and below both said second arm and said ruler, pivoted to the said pivot means on outer end of said second stationary arm with the slotted face so as to adapt said pivoted arm to be swingabl adjustable from a position where its outer base reference face is a longitudinal extension of the base reference face of said stationary arm 'to which "it is connected throughouta ninety degree are inwardly towards the other stationary arm, a graduated arc integral with the pivoted arm on the opposite side from its base reference face, an.ar.cuate channel portion carried on the bod portion of the square to receive therein the depending arc of the :pivoted arm and means for releasably locking said pivoted arm in any set position.

MICHAEL LUIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 165,519 Swasey July 13, 1875 282,583 Starrett Aug. 7, 1883 4133;084 Kelsey 1 July 29, 1890 778,808 Starrett Dec. 27,1904 813,173 Realing Feb. 20, 1906 883,041 McCurdy Mar. 24, 1908 944,799 Lytle Dec. 28, 1909 1,137,838 Cline May 4, 1915 1,286,332 Johns Dec. 3, 1918 1,974,930 Powe Sept. 25, 1934 2,113,524 Wolfe Apr. 5, 1938 

